The present invention relates generally to a pulping process and more particularly to a pulp washing process and a method for controlling the process based on the conductivity of the liquor remaining in the washed pulp at different washing stages. Specifically, the present invention relates to a novel development in probes useful for measuring the conductivity of the liquor in the mat on a pulp washer. The invention is based on the observation that significant gains in economy and quality can be realized by measuring and controlling the soda loss in a pulp washing process continuously and automatically. Toward this end, the conductivity of the liquor remaining in the washed pulp has been found to show good correlation with soda loss in pulp washing, and is, therefore, an attractive control variable if measured correctly and continuously.
Additional background information may be found in prior U.S. Pat. Nos. 4,560,440 and 4,624,742, owned by the present assignee herein, and incorporated by reference in this disclosure. The present invention is an inprovement and/or alternative to the devices shown in the prior patents.